FIG. 1 is a schematic diagram of a wind power generator. Referring to FIG. 1, a wind power generator 1 includes a tower 2, a nacelle 5 formed on an upper portion of the tower 2, and a hub 4 and blades 3 rotatably formed at a front side of the nacelle 5.
Here, the nacelle 5 includes constituent elements which convert torque obtained by the blades 3 into electrical energy.
The nacelle 5 includes a main shaft 6 connected to the blades 3 and the hub 4, a gear box 8 which converts a low speed rotation of the main shaft 6 into a high speed rotation, and a generator 9 connected to the gear box 8, and the main shaft 6, the gear box 8, and the generator 9 are disposed inside a housing 7.
The gear box 8 and the generator 9 are installed and supported on a main frame 11 that is installed on an upper end portion of the tower 2.
The wind power generator having the aforementioned configuration may generate electricity when temperatures of separate components are equal to or higher than operating temperatures.
Among the components, particularly, the gear box part includes a number of gears and bearings, and therefore a lubrication system is installed in the gear box in order to prevent abrasion due to friction between the gears and the bearings.
Here, the lubrication system connected to the gear box includes a lubricant, a heating device, and a cooling device, and is formed to be able to appropriately adjust a temperature of a lubricant supplied into the gear box.
Here, an appropriate operating temperature of the gear box may mean a temperature at which viscosity of a lubricant reaches an appropriate level so that the gears and the bearings inside the gear box may be smoothly operated.
Because viscosity of a lubricant is seriously varied in accordance with a variation in temperature, the gear box is properly protected by a lubricant at a temperature equal to or higher than an appropriate temperature, but at a temperature lower than an appropriate temperature, the gears and the bearings inside the gear box may not be properly protected because of an increase in viscosity of a lubricant.
Accordingly, in a case of operating the gear box, a lubricant is allowed to be heated using the heating device in order to secure an appropriate level of viscosity of the lubricant.
However, a long period of time is needed to heat the lubricant as described above. In other to solve the aforementioned problem, a method of increasing a heating capacity of the heating device was used in the related art in order to allow the lubricant to quickly reach the appropriate temperature.
However, because a larger amount of energy should be supplied to the heating device in order to increase a heating capacity of the heating device as described above, additional energy is needed, but even though the heating capacity is increased by the additional energy, there are many cases in which the lubricant does not quickly reach the appropriate temperature.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.